2020 Hyundai Sonata · symptom sheet
Check engine light or misfire
- 25owner reports
- 47,000median miles
- 0involved a crash
Newest report Jul 10, 2026 · checked Oct 2, 2026
111 of the 178 complaints on this car are about the engine. 25 of those describe misfire, which makes it the most reported problem on the 2020 Sonata.
Tick what matches of 25 reports
Misfire on other Sonata years
Report counts are for each model year on its own, so a newer car has had less time to collect them. Model years with too few reports of it for a sheet: 2019, 2021, 2022, 2023, 2024.
What this problem usually is
These reports start with the check engine light. Many describe the engine running rough or shaking at idle, a P0300-series code, or a catalytic converter code. A worrying number say the light was flashing. Owners often list ignition coils or spark plugs already replaced, and the light coming back afterward.
What got replaced
Owners who name the part that was replaced mention the sensor (3 reports).
Recalls and investigations
2 recalls on the engine cover the 2020 model year. A recall on the same system isn't always the same failure, so read the defect text.
A damaged check valve can allow air to enter the fuel tank, causing it to expand and contact hot exhaust components, melting the tank.
The Remote Smart Parking Assist (RSPA) software may fail to prevent vehicle movement upon detection of an RSPA system malfunction.
All 4 recalls on the 2020 Hyundai Sonata, with the owner complaints on each recalled system
NHTSA investigations into the engine on the Sonata
Loss of motive power. Closed dec 12, 2023.
Engine fires. Closed feb 5, 2024, led to recall 23V-877.
Non-crash vehicle fires. Closed dec 22, 2021, led to recall 20V-061.
Non-crash vehicle fires. Closed may 10, 2019, led to recall 18V-907.
Scope and timeliness. Closed dec 22, 2021, led to recall 17V-226.
Charging system failures. Closed oct 31, 1994.
When it happens
The middle half of failures fell between 3,500 and 82,000 miles, from the 10 reports that gave a mileage.
Is this a known problem?
The manufacturer has sent NHTSA 13 service bulletins or notices for the 2020 Hyundai Sonata that deal with this problem. Newest first.
Federal rules make a manufacturer send NHTSA a copy of any notice about a defect that goes to more than one dealer or owner. Most of these are service bulletins, the repair instructions manufacturers send to dealers. NHTSA generally leaves safety recall bulletins out of this file, and recalls are listed separately.
Some Sonata (DN8, DN8A) vehicles may have DTCs P218100, P2181F0, and/or P2181F1 (Cooling System Performance) set in the Engine Control Module, resulting in an illuminated Check Engine warning lamp.
Certain 2021-2023MY Sonata (DN8) and 2020-2022MY Sonata (DN8A) vehicles may have DTC P0451 stored in the ECU. Follow this bulletin to inspect the check valve, fuel pump cover and fuel tank, and update the ECU.
Certain 2021-2023MY Sonata (DN8) and 2020-2022MY Sonata (DN8A) vehicles may have Diagnostic Trouble Code (DTC) P0451 (also known as DTC P14EE00) stored in the Electronic Control Unit (ECU).
The subject vehicles may have Diagnostic Trouble Code (DTC) P0451 stored in the ECU, which could cause the Check Engine Lamp to come on.
9 more on the 2020 Hyundai Sonata page.
What owners wrote
No report on this problem is short enough to quote in full.
Should you keep driving it?
This page can't tell you that. 0 of 25 reports involved a crash. Owners who file are the ones who had a bad experience, and nobody checks their reports. If the problem affects steering, braking, power or a fire risk, treat it as a safety fault and have it inspected before a long or high-speed drive.
File your own report with NHTSA. Complaint counts are how a problem gets an investigation. How reports land on this sheet.
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